Dynamics of a competitive Lotka-Volterra systems in R3

We describe the dynamics of the 3-dimensional competitive Lotka-Volterra systems x˙=x(a−x−y−z), y˙=y(b−x−y−z), z˙=z(c−x−y−z), providing the phase portraits for all the values of the parameters a, b and c with 0 < a< b< c in the positive octant of the Poincaré ball

Limit cycles of a perturbation of a polynomial Hamiltonian systems of degree 4 symmetric with respect to the origin

We study the number of limit cycles bifurcating from the origin of a Hamiltonian system of degree 4. We prove, using the averaging theory of order 7, that there are quartic polynomial systems close these Hamiltonian systems having 3 limit cycles

Global dynamics of a Lotka-Volterra system in ℝ³

In this work we consider the Lotka-Volterra system in R³ x˙ = −x(x − y − z), y˙ = −y(−x + y − z), z˙ = −z(−x − y + z), introduced recently in [7], and studied also in [8] and [14]. In the first two papers the authors mainly studied the integrability of this differential system, while in the third paper they studied the system as a Hamilton-Poisson system, and also started the analysis of its dynamics. Here we provide the global phase portraits of this 3-dimensional Lotka-Volterra system in the Poincaré ball, that is in R³ adding its extension to the infinity

On the global dynamics of a three-dimensional forced-damped differential system

In this paper by using the Poincaré compactification of ℝ³ we make a global analysis of the model xʹ = ax + y + yz, yʹ = x - ay + bxz, zʹ = cz - bxy. In particular we give the complete description of its dynamics on the infinity sphere. For a + c = 0 or b = 1 this system has invariants. For these values of the parameters we provide the global phase portrait of the system in the Poincaré ball. We also describe the α and ω-limit sets of its orbits in the Poincaré ball

Educación para la ciudadanía y la convivencia Ciclo tres (Quinto, Sexto y Séptimo) : protagonistas de la realidad, dirigimos la historia

El módulo que tenemos entre manos forma parte de una colección cuyo eje de acción es el fortalecimiento y desarrollo de las capacidades que promueven la participación, el empoderamiento y la movilización social para el ejercicio de las ciudadanías en la etapa escolar. Su título, protagonistas de la realidad, dirigimos la historia, inspirado en la frase atribuida a Paulo Freire “aprender a leer la realidad para escribir la historia”, resume el sentido de sus contenidos en dos vertientes, esto es, nos permite orientar los procesos de educación para la ciudadanía y la convivencia de los niños y niñas del ciclo, con el fin de aprender a ubicarse en el medio sociocultural donde se desenvuelve su vida cotidiana, y para actuar sobre el mismo en un sentido transformador. Partimos del reconocimiento de que los seres humanos nos constituimos como tales en relaciones e interacciones. Nuestros vínculos con el resto de la humanidad y el medio natural del cual nos proveemos para existir y con el cual conformamos un todo que hace posible la vida pueden ser más o menos conscientes. La mayor parte del tiempo, estas relaciones nos pasan inadvertidas, por lo lejanas o desconocidas o porque nos acostumbramos a cerrarles los ojos, a taparnos los oídos, a huir de ellas, a no dejarnos afectar por lo que percibimos, hasta llegar a la insensibilidad en su presencia

The bHLH transcription factor SPATULA enables cytokinin signaling, and both activate auxin biosynthesis and transport genes at the medial domain of the gynoecium

[EN] Fruits and seeds are the major food source on earth. Both derive from the gynoecium and, therefore, it is crucial to understand the mechanisms that guide the development of this organ of angiosperm species. In Arabidopsis, the gynoecium is composed of two congenitally fused carpels, where two domains: medial and lateral, can be distinguished. The medial domain includes the carpel margin meristem (CMM) that is key for the production of the internal tissues involved in fertilization, such as septum, ovules, and transmitting tract. Interestingly, the medial domain shows a high cytokinin signaling output, in contrast to the lateral domain, where it is hardly detected. While it is known that cytokinin provides meristematic properties, understanding on the mechanisms that underlie the cytokinin signaling pattern in the young gynoecium is lacking. Moreover, in other tissues, the cytokinin pathway is often connected to the auxin pathway, but we also lack knowledge about these connections in the young gynoecium. Our results reveal that cytokinin signaling, that can provide meristematic properties required for CMM activity and growth, is enabled by the transcription factor SPATULA (SPT) in the medial domain. Meanwhile, cytokinin signaling is confined to the medial domain by the cytokinin response repressor ARABIDOPSIS HISTIDINE PHOSPHOTRANSFERASE 6 (AHP6), and perhaps by ARR16 (a type-A ARR) as well, both present in the lateral domains (presumptive valves) of the developing gynoecia. Moreover, SPT and cytokinin, probably together, promote the expression of the auxin biosynthetic gene TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 (TAA1) and the gene encoding the auxin efflux transporter PIN-FORMED 3 (PIN3), likely creating auxin drainage important for gynoecium growth. This study provides novel insights in the spatiotemporal determination of the cytokinin signaling pattern and its connection to the auxin pathway in the young gynoecium.IRO, VMZM, HHU and PLS were supported by the Mexican National Council of Science and Technology (CONACyT) with a PhD fellowship (210085, 210100, 243380 and 219883, respectively). Work in the SDF laboratory was financed by the CONACyT grants CB-2012-177739, FC-2015-2/1061, and INFR-2015-253504, and NMM by the CONACyT grant CB-2011-165986. SDF, CF and LC acknowledge the support of the European Union FP7-PEOPLE-2009-IRSES project EVOCODE (grant no. 247587) and H2020-MSCARISE-2015 project ExpoSEED (grant no. 691109). SDF also acknowledges the Marine Biological Laboratory (MBL) in Woods Hole for a scholarship for the Gene Regulatory Networks for Development Course 2015 (GERN2015). IE acknowledges the International European Fellowship-METMADS project and the Universita degli Studi di Milano (RTD-A; 2016). Research in the laboratory of MFY was funded by NSF (grant IOS-1121055), NIH (grant 1R01GM112976-01A1) and the Paul D. Saltman Endowed Chair in Science Education (MFY). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Reyes Olalde, J.; Zuñiga, V.; Serwatowska, J.; Chávez Montes, R.; Lozano-Sotomayor, P.; Herrera-Ubaldo, H.; Gonzalez Aguilera, K.... (2017). The bHLH transcription factor SPATULA enables cytokinin signaling, and both activate auxin biosynthesis and transport genes at the medial domain of the gynoecium. PLoS Genetics. 13(4):1-31. https://doi.org/10.1371/journal.pgen.1006726S131134Reyes-Olalde, J. I., Zuñiga-Mayo, V. M., Chávez Montes, R. A., Marsch-Martínez, N., & de Folter, S. (2013). Inside the gynoecium: at the carpel margin. Trends in Plant Science, 18(11), 644-655. doi:10.1016/j.tplants.2013.08.002Alvarez-Buylla, E. R., Benítez, M., Corvera-Poiré, A., Chaos Cador, Á., de Folter, S., Gamboa de Buen, A., … Sánchez-Corrales, Y. E. (2010). Flower Development. The Arabidopsis Book, 8, e0127. doi:10.1199/tab.0127Bowman, J. L., Baum, S. F., Eshed, Y., Putterill, J., & Alvarez, J. (1999). 4 Molecular Genetics of Gynoecium Development in Arabidopsis. Current Topics in Developmental Biology Volume 45, 155-205. doi:10.1016/s0070-2153(08)60316-6Chávez Montes, R. A., Herrera-Ubaldo, H., Serwatowska, J., & de Folter, S. (2015). Towards a comprehensive and dynamic gynoecium gene regulatory network. Current Plant Biology, 3-4, 3-12. doi:10.1016/j.cpb.2015.08.002Marsch-Martínez, N., & de Folter, S. (2016). Hormonal control of the development of the gynoecium. Current Opinion in Plant Biology, 29, 104-114. doi:10.1016/j.pbi.2015.12.006Marsch-Martínez, N., Ramos-Cruz, D., Irepan Reyes-Olalde, J., Lozano-Sotomayor, P., Zúñiga-Mayo, V. M., & de Folter, S. (2012). The role of cytokinin during Arabidopsis gynoecia and fruit morphogenesis and patterning. The Plant Journal, 72(2), 222-234. doi:10.1111/j.1365-313x.2012.05062.xZhao, Z., Andersen, S. U., Ljung, K., Dolezal, K., Miotk, A., Schultheiss, S. J., & Lohmann, J. U. (2010). Hormonal control of the shoot stem-cell niche. Nature, 465(7301), 1089-1092. doi:10.1038/nature09126Ashikari, M. (2005). Cytokinin Oxidase Regulates Rice Grain Production. Science, 309(5735), 741-745. doi:10.1126/science.1113373Bartrina, I., Otto, E., Strnad, M., Werner, T., & Schmülling, T. (2011). Cytokinin Regulates the Activity of Reproductive Meristems, Flower Organ Size, Ovule Formation, and Thus Seed Yield in Arabidopsis thaliana. The Plant Cell, 23(1), 69-80. doi:10.1105/tpc.110.079079Hwang, I., Sheen, J., & Müller, B. (2012). Cytokinin Signaling Networks. Annual Review of Plant Biology, 63(1), 353-380. doi:10.1146/annurev-arplant-042811-105503Schaller, G. E., Bishopp, A., & Kieber, J. J. (2015). The Yin-Yang of Hormones: Cytokinin and Auxin Interactions in Plant Development. The Plant Cell, 27(1), 44-63. doi:10.1105/tpc.114.133595Kieber, J. J., & Schaller, G. E. (2010). The Perception of Cytokinin: A Story 50 Years in the Making: Figure 1. Plant Physiology, 154(2), 487-492. doi:10.1104/pp.110.161596Long, J. A., Moan, E. I., Medford, J. I., & Barton, M. K. (1996). A member of the KNOTTED class of homeodomain proteins encoded by the STM gene of Arabidopsis. Nature, 379(6560), 66-69. doi:10.1038/379066a0Jasinski, S., Piazza, P., Craft, J., Hay, A., Woolley, L., Rieu, I., … Tsiantis, M. (2005). KNOX Action in Arabidopsis Is Mediated by Coordinate Regulation of Cytokinin and Gibberellin Activities. Current Biology, 15(17), 1560-1565. doi:10.1016/j.cub.2005.07.023Yanai, O., Shani, E., Dolezal, K., Tarkowski, P., Sablowski, R., Sandberg, G., … Ori, N. (2005). Arabidopsis KNOXI Proteins Activate Cytokinin Biosynthesis. Current Biology, 15(17), 1566-1571. doi:10.1016/j.cub.2005.07.060Scofield, S., Dewitte, W., Nieuwland, J., & Murray, J. A. H. (2013). The Arabidopsis homeobox gene SHOOT MERISTEMLESS has cellular and meristem-organisational roles with differential requirements for cytokinin and CYCD3 activity. The Plant Journal, 75(1), 53-66. doi:10.1111/tpj.12198Gordon, S. P., Chickarmane, V. S., Ohno, C., & Meyerowitz, E. M. (2009). Multiple feedback loops through cytokinin signaling control stem cell number within the Arabidopsis shoot meristem. Proceedings of the National Academy of Sciences, 106(38), 16529-16534. doi:10.1073/pnas.0908122106Chickarmane, V. S., Gordon, S. P., Tarr, P. T., Heisler, M. G., & Meyerowitz, E. M. (2012). Cytokinin signaling as a positional cue for patterning the apical-basal axis of the growing Arabidopsis shoot meristem. Proceedings of the National Academy of Sciences, 109(10), 4002-4007. doi:10.1073/pnas.1200636109Leibfried, A., To, J. P. C., Busch, W., Stehling, S., Kehle, A., Demar, M., … Lohmann, J. U. (2005). WUSCHEL controls meristem function by direct regulation of cytokinin-inducible response regulators. Nature, 438(7071), 1172-1175. doi:10.1038/nature04270Werner, T., Motyka, V., Laucou, V., Smets, R., Van Onckelen, H., & Schmülling, T. (2003). Cytokinin-Deficient Transgenic Arabidopsis Plants Show Multiple Developmental Alterations Indicating Opposite Functions of Cytokinins in the Regulation of Shoot and Root Meristem Activity. The Plant Cell, 15(11), 2532-2550. doi:10.1105/tpc.014928Larsson, E., Franks, R. G., & Sundberg, E. (2013). Auxin and the Arabidopsis thaliana gynoecium. Journal of Experimental Botany, 64(9), 2619-2627. doi:10.1093/jxb/ert099Weijers, D., & Wagner, D. (2016). Transcriptional Responses to the Auxin Hormone. Annual Review of Plant Biology, 67(1), 539-574. doi:10.1146/annurev-arplant-043015-112122Robert, H. S., Crhak Khaitova, L., Mroue, S., & Benková, E. (2015). The importance of localized auxin production for morphogenesis of reproductive organs and embryos inArabidopsis. Journal of Experimental Botany, 66(16), 5029-5042. doi:10.1093/jxb/erv256Kuusk, S., Sohlberg, J. J., Magnus Eklund, D., & Sundberg, E. (2006). Functionally redundantSHIfamily genes regulate Arabidopsis gynoecium development in a dose-dependent manner. The Plant Journal, 47(1), 99-111. doi:10.1111/j.1365-313x.2006.02774.xSohlberg, J. J., Myrenås, M., Kuusk, S., Lagercrantz, U., Kowalczyk, M., Sandberg, G., & Sundberg, E. (2006). STY1regulates auxin homeostasis and affects apical-basal patterning of the Arabidopsis gynoecium. The Plant Journal, 47(1), 112-123. doi:10.1111/j.1365-313x.2006.02775.xStåldal, V., Sohlberg, J. J., Eklund, D. M., Ljung, K., & Sundberg, E. (2008). Auxin can act independently ofCRC,LUG,SEU,SPTandSTY1in style development but not apical-basal patterning of theArabidopsisgynoecium. New Phytologist, 180(4), 798-808. doi:10.1111/j.1469-8137.2008.02625.xVan Gelderen, K., van Rongen, M., Liu, A., Otten, A., & Offringa, R. (2016). An INDEHISCENT-Controlled Auxin Response Specifies the Separation Layer in Early Arabidopsis Fruit. Molecular Plant, 9(6), 857-869. doi:10.1016/j.molp.2016.03.005José Ripoll, J., Bailey, L. J., Mai, Q.-A., Wu, S. L., Hon, C. T., Chapman, E. J., … Yanofsky, M. F. (2015). microRNA regulation of fruit growth. Nature Plants, 1(4). doi:10.1038/nplants.2015.36Larsson, E., Roberts, C. J., Claes, A. R., Franks, R. G., & Sundberg, E. (2014). Polar Auxin Transport Is Essential for Medial versus Lateral Tissue Specification and Vascular-Mediated Valve Outgrowth in Arabidopsis Gynoecia. Plant Physiology, 166(4), 1998-2012. doi:10.1104/pp.114.245951Nole-Wilson, S., Azhakanandam, S., & Franks, R. G. (2010). Polar auxin transport together with AINTEGUMENTA and REVOLUTA coordinate early Arabidopsis gynoecium development. Developmental Biology, 346(2), 181-195. doi:10.1016/j.ydbio.2010.07.016De Folter, S. (2016). Auxin Is Required for Valve Margin Patterning in Arabidopsis After All. Molecular Plant, 9(6), 768-770. doi:10.1016/j.molp.2016.05.005Moubayidin, L., & Østergaard, L. (2014). Dynamic Control of Auxin Distribution Imposes a Bilateral-to-Radial Symmetry Switch during Gynoecium Development. Current Biology, 24(22), 2743-2748. doi:10.1016/j.cub.2014.09.080Girin, T., Paicu, T., Stephenson, P., Fuentes, S., Körner, E., O’Brien, M., … Østergaard, L. (2011). INDEHISCENT and SPATULA Interact to Specify Carpel and Valve Margin Tissue and Thus Promote Seed Dispersal in Arabidopsis. The Plant Cell, 23(10), 3641-3653. doi:10.1105/tpc.111.090944Ioio, R. D., Nakamura, K., Moubayidin, L., Perilli, S., Taniguchi, M., Morita, M. T., … Sabatini, S. (2008). A Genetic Framework for the Control of Cell Division and Differentiation in the Root Meristem. Science, 322(5906), 1380-1384. doi:10.1126/science.1164147Bishopp, A., Help, H., El-Showk, S., Weijers, D., Scheres, B., Friml, J., … Helariutta, Y. (2011). A Mutually Inhibitory Interaction between Auxin and Cytokinin Specifies Vascular Pattern in Roots. Current Biology, 21(11), 917-926. doi:10.1016/j.cub.2011.04.017De Rybel, B., Adibi, M., Breda, A. S., Wendrich, J. R., Smit, M. E., Novák, O., … Weijers, D. (2014). Integration of growth and patterning during vascular tissue formation in Arabidopsis. Science, 345(6197), 1255215. doi:10.1126/science.1255215Pernisova, M., Klima, P., Horak, J., Valkova, M., Malbeck, J., Soucek, P., … Hejatko, J. (2009). Cytokinins modulate auxin-induced organogenesis in plants via regulation of the auxin efflux. Proceedings of the National Academy of Sciences, 106(9), 3609-3614. doi:10.1073/pnas.0811539106Cheng, Z. J., Wang, L., Sun, W., Zhang, Y., Zhou, C., Su, Y. H., … Zhang, X. S. (2012). Pattern of Auxin and Cytokinin Responses for Shoot Meristem Induction Results from the Regulation of Cytokinin Biosynthesis by AUXIN RESPONSE FACTOR3. Plant Physiology, 161(1), 240-251. doi:10.1104/pp.112.203166Alvarez, J., & Smyth, D. R. (2002). CRABS CLAWandSPATULAGenes Regulate Growth and Pattern Formation during Gynoecium Development inArabidopsis thaliana. International Journal of Plant Sciences, 163(1), 17-41. doi:10.1086/324178Groszmann, M., Bylstra, Y., Lampugnani, E. R., & Smyth, D. R. (2010). Regulation of tissue-specific expression of SPATULA, a bHLH gene involved in carpel development, seedling germination, and lateral organ growth in Arabidopsis. Journal of Experimental Botany, 61(5), 1495-1508. doi:10.1093/jxb/erq015Smyth, D. R., Bowman, J. L., & Meyerowitz, E. M. (1990). Early flower development in Arabidopsis. The Plant Cell, 2(8), 755-767. doi:10.1105/tpc.2.8.755Müller, B., & Sheen, J. (2008). Cytokinin and auxin interaction in root stem-cell specification during early embryogenesis. Nature, 453(7198), 1094-1097. doi:10.1038/nature06943Argyros, R. D., Mathews, D. E., Chiang, Y.-H., Palmer, C. M., Thibault, D. M., Etheridge, N., … Schaller, G. E. (2008). Type B Response Regulators of Arabidopsis Play Key Roles in Cytokinin Signaling and Plant Development. The Plant Cell, 20(8), 2102-2116. doi:10.1105/tpc.108.059584Mason, M. G., Mathews, D. E., Argyros, D. A., Maxwell, B. B., Kieber, J. J., Alonso, J. M., … Schaller, G. E. (2005). Multiple Type-B Response Regulators Mediate Cytokinin Signal Transduction in Arabidopsis. The Plant Cell, 17(11), 3007-3018. doi:10.1105/tpc.105.035451Ishida, K., Yamashino, T., Yokoyama, A., & Mizuno, T. (2008). Three Type-B Response Regulators, ARR1, ARR10 and ARR12, Play Essential but Redundant Roles in Cytokinin Signal Transduction Throughout the Life Cycle of Arabidopsis thaliana. Plant and Cell Physiology, 49(1), 47-57. doi:10.1093/pcp/pcm165Yokoyama, A., Yamashino, T., Amano, Y.-I., Tajima, Y., Imamura, A., Sakakibara, H., & Mizuno, T. (2006). Type-B ARR Transcription Factors, ARR10 and ARR12, are Implicated in Cytokinin-Mediated Regulation of Protoxylem Differentiation in Roots of Arabidopsis thaliana. Plant and Cell Physiology, 48(1), 84-96. doi:10.1093/pcp/pcl040Schuster, C., Gaillochet, C., & Lohmann, J. U. (2015). Arabidopsis HECATE genes function in phytohormone control during gynoecium development. Development, 142(19), 3343-3350. doi:10.1242/dev.120444Toledo-Ortiz, G., Huq, E., & Quail, P. H. (2003). The Arabidopsis Basic/Helix-Loop-Helix Transcription Factor Family. The Plant Cell, 15(8), 1749-1770. doi:10.1105/tpc.013839Reymond, M. C., Brunoud, G., Chauvet, A., Martínez-Garcia, J. F., Martin-Magniette, M.-L., Monéger, F., & Scutt, C. P. (2012). A Light-Regulated Genetic Module Was Recruited to Carpel Development in Arabidopsis following a Structural Change to SPATULA. The Plant Cell, 24(7), 2812-2825. doi:10.1105/tpc.112.097915Ballester, P., Navarrete-Gómez, M., Carbonero, P., Oñate-Sánchez, L., & Ferrándiz, C. (2015). Leaf expansion in Arabidopsis is controlled by a TCP-NGA regulatory module likely conserved in distantly related species. Physiologia Plantarum, 155(1), 21-32. doi:10.1111/ppl.12327Hellens, R., Allan, A., Friel, E., Bolitho, K., Grafton, K., Templeton, M., … Laing, W. (2005). Plant Methods, 1(1), 13. doi:10.1186/1746-4811-1-13Makkena, S., & Lamb, R. S. (2013). The bHLH transcription factor SPATULA regulates root growth by controlling the size of the root meristem. BMC Plant Biology, 13(1), 1. doi:10.1186/1471-2229-13-1Stepanova, A. N., Robertson-Hoyt, J., Yun, J., Benavente, L. M., Xie, D.-Y., Doležal, K., … Alonso, J. M. (2008). TAA1-Mediated Auxin Biosynthesis Is Essential for Hormone Crosstalk and Plant Development. Cell, 133(1), 177-191. doi:10.1016/j.cell.2008.01.047Bhargava, A., Clabaugh, I., To, J. P., Maxwell, B. B., Chiang, Y.-H., Schaller, G. E., … Kieber, J. J. (2013). Identification of Cytokinin-Responsive Genes Using Microarray Meta-Analysis and RNA-Seq in Arabidopsis. Plant Physiology, 162(1), 272-294. doi:10.1104/pp.113.217026Sakai, H., Aoyama, T., & Oka, A. (2000). Arabidopsis ARR1 and ARR2 response regulators operate as transcriptional activators. The Plant Journal, 24(6), 703-711. doi:10.1046/j.1365-313x.2000.00909.xSakai, H. (2001). ARR1, a Transcription Factor for Genes Immediately Responsive to Cytokinins. Science, 294(5546), 1519-1521. doi:10.1126/science.1065201Moubayidin, L., Di Mambro, R., Sozzani, R., Pacifici, E., Salvi, E., Terpstra, I., … Sabatini, S. (2013). Spatial Coordination between Stem Cell Activity and Cell Differentiation in the Root Meristem. Developmental Cell, 26(4), 405-415. doi:10.1016/j.devcel.2013.06.025Benková, E., Michniewicz, M., Sauer, M., Teichmann, T., Seifertová, D., Jürgens, G., & Friml, J. (2003). Local, Efflux-Dependent Auxin Gradients as a Common Module for Plant Organ Formation. Cell, 115(5), 591-602. doi:10.1016/s0092-8674(03)00924-3Okada, K., Ueda, J., Komaki, M. K., Bell, C. J., & Shimura, Y. (1991). Requirement of the Auxin Polar Transport System in Early Stages of Arabidopsis Floral Bud Formation. The Plant Cell, 677-684. doi:10.1105/tpc.3.7.677Blilou, I., Xu, J., Wildwater, M., Willemsen, V., Paponov, I., Friml, J., … Scheres, B. (2005). The PIN auxin efflux facilitator network controls growth and patterning in Arabidopsis roots. Nature, 433(7021), 39-44. doi:10.1038/nature03184Mahonen, A. P. (2006). Cytokinin Signaling and Its Inhibitor AHP6 Regulate Cell Fate During Vascular Development. Science, 311(5757), 94-98. doi:10.1126/science.1118875Besnard, F., Refahi, Y., Morin, V., Marteaux, B., Brunoud, G., Chambrier, P., … Vernoux, T. (2013). Cytokinin signalling inhibitory fields provide robustness to phyllotaxis. Nature, 505(7483), 417-421. doi:10.1038/nature12791Longabaugh, W. J. R., Davidson, E. H., & Bolouri, H. (2005). Computational representation of developmental genetic regulatory networks. Developmental Biology, 283(1), 1-16. doi:10.1016/j.ydbio.2005.04.023Faure, E., Peter, I. S., & Davidson, E. H. (2013). A New Software Package for Predictive Gene Regulatory Network Modeling and Redesign. Journal of Computational Biology, 20(6), 419-423. doi:10.1089/cmb.2012.0297Mangan, S., & Alon, U. (2003). Structure and function of the feed-forward loop network motif. Proceedings of the National Academy of Sciences, 100(21), 11980-11985. doi:10.1073/pnas.2133841100Chen, Q., Liu, Y., Maere, S., Lee, E., Van Isterdael, G., Xie, Z., … Vanneste, S. (2015). A coherent transcriptional feed-forward motif model for mediating auxin-sensitive PIN3 expression during lateral root development. Nature Communications, 6(1). doi:10.1038/ncomms9821Qiu, K., Li, Z., Yang, Z., Chen, J., Wu, S., Zhu, X., … Zhou, X. (2015). EIN3 and ORE1 Accelerate Degreening during Ethylene-Mediated Leaf Senescence by Directly Activating Chlorophyll Catabolic Genes in Arabidopsis. PLOS Genetics, 11(7), e1005399. doi:10.1371/journal.pgen.1005399Seaton, D. D., Smith, R. W., Song, Y. H., MacGregor, D. R., Stewart, K., Steel, G., … Halliday, K. J. (2015). Linked circadian outputs control elongation growth and flowering in response to photoperiod and temperature. Molecular Systems Biology, 11(1), 776. doi:10.15252/msb.20145766Roeder, A. H. K., & Yanofsky, M. F. (2006). Fruit Development in Arabidopsis. The Arabidopsis Book, 4, e0075. doi:10.1199/tab.0075Marsch-Martínez, N., Reyes-Olalde, J. I., Ramos-Cruz, D., Lozano-Sotomayor, P., Zúñiga-Mayo, V. M., & de Folter, S. (2012). Hormones talking. Plant Signaling & Behavior, 7(12), 1698-1701. doi:10.4161/psb.22422Balanza, V., Navarrete, M., Trigueros, M., & Ferrandiz, C. (2006). Patterning the female side of Arabidopsis: the importance of hormones. Journal of Experimental Botany, 57(13), 3457-3469. doi:10.1093/jxb/erl188Kamiuchi, Y., Yamamoto, K., Furutani, M., Tasaka, M., & Aida, M. (2014). The CUC1 and CUC2 genes promote carpel margin meristem formation during Arabidopsis gynoecium development. Frontiers in Plant Science, 5. doi:10.3389/fpls.2014.00165Scofield, S., Dewitte, W., & Murray, J. A. H. (2007). The KNOX gene SHOOT MERISTEMLESS is required for the development of reproductive meristematic tissues in Arabidopsis. The Plant Journal, 50(5), 767-781. doi:10.1111/j.1365-313x.2007.03095.xLi, K., Yu, R., Fan, L.-M., Wei, N., Chen, H., & Deng, X. W. (2016). DELLA-mediated PIF degradation contributes to coordination of light and gibberellin signalling in Arabidopsis. Nature Communications, 7(1). doi:10.1038/ncomms11868Oh, E., Zhu, J.-Y., & Wang, Z.-Y. (2012). Interaction between BZR1 and PIF4 integrates brassinosteroid and environmental responses. Nature Cell Biology, 14(8), 802-809. doi:10.1038/ncb2545Sharma, N., Xin, R., Kim, D.-H., Sung, S., Lange, T., & Huq, E. (2016). NO FLOWERING IN SHORT DAY (NFL) is a bHLH transcription factor that promotes flowering specifically under short-day conditions inArabidopsis. Development, 143(4), 682-690. doi:10.1242/dev.128595Varaud, E., Brioudes, F., Szécsi, J., Leroux, J., Brown, S., Perrot-Rechenmann, C., & Bendahmane, M. (2011). AUXIN RESPONSE FACTOR8 Regulates Arabidopsis Petal Growth by Interacting with the bHLH Transcription Factor BIGPETALp. The Plant Cell, 23(3), 973-983. doi:10.1105/tpc.110.081653Savaldi-Goldstein, S., & Chory, J. (2008). Growth coordination and the shoot epidermis. Current Opinion in Plant Biology, 11(1), 42-48. doi:10.1016/j.pbi.2007.10.009Schuster, C., Gaillochet, C., Medzihradszky, A., Busch, W., Daum, G., Krebs, M., … Lohmann, J. U. (2014). A Regulatory Framework for Shoot Stem Cell Co

Women in (Dis)placement: The Field of Studies on Migrations, Social Remittances, Care and Gender in Chile

This article presents current perspectives on the gender approach to the study of migration in Chile between 1990 and 2018, contextualizing it in light of international debates in the social sciences. We will discuss how the feminization and the growth of Latin American migrations have given rise to a prolific field of research, as exemplified by studies conducted in central and northern Chile. We will show how the concepts of social remittances and caregiving permeate the Chilean debate on migrant women. We conclude with reflections on topics and perspectives to be incorporated into the Chilean research agenda on gender and migration.Se presenta un estado del arte sobre el enfoque de género en los estudios de la migración en Chile entre 1990 y 2018, contextualizándolo a la luz de debates internacionales de las ciencias sociales. Abordaremos cómo la feminización y el incremento de las migraciones latinoamericanas inauguran un prolijo campo de investigaciones, articulado a través de estudios desarrollados en el centro y en el norte de Chile. Señalaremos cómo los conceptos de remesas sociales y cuidados permean el debate chileno sobre las mujeres migrantes. Finalizamos con reflexiones sobre temas y perspectivas a ser incorporados en la agenda chilena de investigaciones sobre género y migración.The authors would like to thank the Chilean National Commission for Scientific and Technological Research (CONICYT) for funding the study that led to this article through Fondecyt Regular Project number 1160683: “Ser Mujer Mayor en Santiago. Organización social de los cuidados, feminización del envejecimiento y desigualdades acumuladas” (“Being an older woman in Santiago. Social organization of care, feminization of ageing and accumulated inequalities”), led by Herminia Gonzálvez Torralbo and Fondecyt Regular Project number 1190056: “The Boundaries of Gender Violence: Migrant Women’s Experiences in South American Border Territories” led by Menara Lube Guizardi

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries(1,2). However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world(3) and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health(4,5). However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol-which is a marker of cardiovascular riskchanged from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million-4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.Peer reviewe

Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at root s(NN)=2.76TeV

Peer reviewe